The Evolution of Oak Ageing in Rioja Red Wines
- By Jacky Blisson MW
- 20 Oct 2020
- 5 MIN
- Level 101
Throughout the last century the red wines of Rioja were famous for their mellow palate profiles and sweet vanilla flavours imparted by extended ageing in American oak. Over time, the duration of barrel maturation became the primary indicator of quality in the region.
Until the 18th century oak barrels were only used to transport Rioja wines to export markets. These vessels were lined with resins that tainted the wines’ flavour. The use of oak in the region changed after several respected local wine producers traveled to Bordeaux in the mid-1800s to visit châteaux and consult with their winemakers. They brought back the technique of barrel maturation, a practice which quickly gained favour amongst Rioja’s winemaking community.
However, by the early 1900s French oak barrels were becoming increasingly cost prohibitive. Thus, wine producers began transitioning to American oak, which could be acquired cheaply in Spain’s overseas colonies. The oak was brought over as planks and was then fashioned into barrels by local cooperages.
Rioja Wine Ageing Classifications
Historically, the length of barrel ageing differed radically from one cuvée, or winery, to another. Some wines were released shortly after harvest in a fresh and fruity style, while others would be aged in barrel for decades. Consumers had no way of knowing which style of Rioja they would be getting.
Just over forty years ago, specific labeling legislation came into effect bringing more consistency and clarity to Rioja wine ageing. The regulations divided Rioja into four tiers based upon ageing requirements:
- Joven: No minimum ageing rules.
- Crianza: 2 years’ minimum ageing (at least 1 year in barrel before release).
- Reserva: 3 years’ minimum ageing (at least 1 year in barrel and 6 months in bottle before release).
- Gran Reserva: 5 years’ minimum ageing (at least 2 years in barrel and 2 years in bottle before release).
American vs. French Oak Characteristics
American oak comes from a variety of oak called Quercus alba, or white oak, which is native to Eastern and Central parts of the United States. American oak barrels contain higher concentrations of flavour compounds like lactone and vanillin as compared to their French oak counterparts. Lactones impart coconut and dill notes at high levels. Vanillin, the main flavour component in vanilla beans, gives sweet, fragrant vanilla notes. New American oak can impart astringent tannins to young wines, athough this softens over time.
French oak barrels are sourced from two main oak tree varieties: Quercus petraea and Quercus robur, found primarily in the Allier, Limousin, Nevers, Tronçais, and Vosges forests of France. They possess a tighter grain than American oak. In general, French oak barrels impart more subtle vanilla, spice, and/or cedar aromas and a more integrated, finer quality of tannin.
The Evolution of American Oak in Rioja
The wines of Rioja were synonymous with American oak and its heady flavours throughout the 1900s. Wines that aged for long periods in barrel, the Gran Reservas, were glossy and soft on the palate, with oxidative (nutty, dried fruit) flavours, overlaid by intense vanilla and coconut American oak notes.
The economic boom of the 1980s and 1990s, followed by a swing in global wine fashion toward bold, fruit-forward wines, led to the re-introduction of French oak barrels in Rioja. At the same time, Rioja growers started lowering yields and harvesting later for increased ripeness. A growing terroir-oriented movement was also taking hold.
Traditional, Modern, and Post-Modern Rioja
For a time, Rioja wines fell into two camps: traditional wines that, depending on their ageing period, were pale, soft, and American oak scented vs. modern wines, with deeper colours, more youthful fruity aromas, firmer structures, and subtle French oak influences. Those divisions are far less marked in Rioja today.
In 2018, Rioja unveiled a new, origin-based wine classification system, establishing a quality hierarchy in the French appellation manner, from regional, to sub-regional, to superior single vineyards. These new DOC rules do not replace the old ageing classifications but rather sit alongside them. Many producers now use both American and French oak to age their wines and produce a wide variety of styles that reflect individual vineyard sites.